The dielectric image waveguiding structure is generally known in the microwave industry and includes a rectangular strip of either a dielectric material or high resistivity semiconductive material of predetermined rectangular cross section and mounted on a metal ground plane (also referred to as an "image plane") of infinite area. The dielectric or semiconductive rectangular strip is generally referred to in the art as the image guide and is useful for coupling microwave or millimeter wave energy from point to point on the ground or image plane. This image guide requires no surface metallization to control or confine the propagation of energy within the image guide, as in the case, for example, of the stripline or microstrip type of waveguide structures. The dielectric image structure of the type disclosed herein was disclosed as early as 1958 in an article by S. P. Schlesinger et al entitled "Dielectric Image Lines", IRE Transactions on Microwave Theory and Techniques, July 1958, at page 29 et seq. Further examples of such image guide structures are disclosed in FIG. 1c of U.S. Pat. No. 3,903,488 and in our copending application Ser. No. 632,613 filed Nov. 14, 1975, and also by E. A. J. Marcatili in an article entitled "Dielectric Rectangular Waveguide and Directional Coupler for Integrated Optics", The Bell System Technical Journal, Sept. 1969, at page 2071 et seq.
The dielectric image guide of the above type is particularly useful in sustaining the fundamental E.sub.y.sup.11 mode of millimeter wave propagation in the millimeter wave frequency range of 30 to 300 GHz. The particular cross section height and width dimensions of the image guide are, of course, dependent upon the particular frequency or frequency range of interest within the above 30 to 300 GHz range. That is, the specific contour of the electric (E) field of this E.sub.y.sup.11 fundamental mode of wave propagation will vary with frequency, so that the height and width dimensions of the image guide can be tailored to correspond to a particular E-field contour and thereby provide the most efficient transmission of microwave or millimeter wave energy within the image guide.
In certain millimeter wave integrated circuit applications, it is desirable to provide either frequency mixing and conversion or detection of the energy propagated in the image guide, and it is generally known that mixer diodes can be mounted in the path of the energy propagated in the image guide to provide either or both of these two functions. For example, when a mixer or detector diode is so mounted and connected in a known detector circuit, it will function to develop an output voltage which is proportional to the input power received from the image guide.